Avicenna (Ibn Sina) (980–1037), Persian (Iranian) philosopher and physician, regarded as the greatest of the medieval Islamic philosophers, served as court physician for the Sultan of Bukhara. He was deeply influenced by Aristotle and still maintained a Muslim faith. He is best known for his distinction between essence and existence, in which the essences of existing things must be explained by their existing cause(s), whose reality is higher than the perceived essence. In the short selection he discusses the conflict between the philosophical and theological perspective.
In the name of God, the Merciful, the Compassionate.
Someone asked the eminent shaykh Abū 'Alī b. Sīnā (may God the Exalted have mercy on him) the meaning of the Sūfī saying, 'He who knows the secret of destiny is an atheist'. In reply he stated that this matter contains the utmost obscurity, and is one of those matters which may be set down only in enigmatic form and taught only in a hidden manner, on account of the corrupting effects its open declaration would have on the general public. The basic principle concerning it is found in a Tradition of the Prophet (God bless and safeguard him): 'Destiny is the secret of God; do not declare the secret of God'. In another Tradition, when a man questioned the Prince of the Believers, 'Alī (may God be pleased with him), he replied, 'Destiny is a deep sea; do not sail out on it'. Being asked again he replied, 'It is a stony path; do not walk on it'. Being asked once more he said, 'It is a hard ascent; do not undertake it'.1
The shaykh said: Know that the secret of destiny is based upon certain premisses, such as  the world order,  the report2 that there is Reward and Punishment, and  the affirmation of the resurrection of souls.
1. The first premiss is that you should know that in the world as a whole and in its parts, both upper and earthly, there is nothing which forms an excep-
1 These Traditions do not explain the meaning of the orig-
inal saying, they merely reaffirm the prohibition.
2'Report' (hadīth) seems to hint that after-life Reward and
Punishment in the usual sense are only traditional doc-
trines, not known by science. This view is confirmed be-
low, and elsewhere, e.g. Shifā ': Ilāhiyyāt, ed. I. Madkur,
M. Y. Musa, S. Dunya, and S. Zayed, Cairo, 1960, IX, 7,
pp. 414 ff.
Reprinted by permission from Avicenna, Essay on the Secret of Destiny, translated by George Hourani in Bulletin of the School
of Oriental and African Studies, London, vol. 29, Pt. 1, 1996, pp. 31–33.